File extensions – definition and basic information


File extensions are the integral parts of the files that are on each computer. Often, when working on a computer, we encounter a wide range of files, such as docx, ppt, part, mp3 or rmvb. We realize that they are there – but we often do not know what they are for on our computer.

File extension, also known as the filename extension is a suffix added to the name of a computer file, usually consisting of a number of characters placed after the last dot in the filename, which gives us information about its coding. In other words a file extension is a file format. It allows the operating system (e.g. Windows) to recognize what program it should try to open the file.

In the table below you will find a random selection of popular file extensions.


File extension The full name of the file Category

CSV file extension

Comma Separated Values File

Data Files

DBF file extension

Database File

Database Files

DTD file extension

Document Type Definition File

Developer Files

EPS file extension

Encapsulated PostScript File

Vector Image Files

EPUB file extension

Open eBook File

eBook Files

EXE file extension

Windows Executable File

Executable Files

FON file extension

Generic Font File

Font Files

MAX file extension

3ds Max Scene File

3D Image Files

NES file extension

Nintendo (NES) ROM File

Game Files

OTF file extension

OpenType Font

Font Files

SVG file extension

Scalable Vector Graphics File

Vector Image Files

TEX file extension

LaTeX Source Document

Text Files

TTF file extension

TrueType Font

Font Files

WMA file extension

Windows Media Audio File

Audio Files

3DS file extension

3D Studio Scene

3D Image Files